One specific study mentioned indirectly here by Smith is a paper that examined gene transfer and survival in the human gut, titled “Assessing the Survival of Transgenic Plant DNA in the Human Gastrointestinal Tract“. It’s quite a useful study, but not for the reasons Smith seems to be using it for. He claims that the study showed gene transfer – but neglected to mention some key facts about the design of the study. Do you know what an ileostomy is? “An ileostomy is a surgical opening constructed by bringing the end or loop of small intestine (the ileum) out onto the surface of the skin.”[96] The reason you need to understand what this is is because the study Smith used was carried out in part on ileostomists. This is a very important thing to understand because the bowel system of ileostomists is not comparable to a normal human bowel system. The study found that both the non-transgenic and the transgenic DNA was detectable in the ileostomists. However, when the study was done on people with normal bowel function, they discovered that their waste was free of all genes – indicating that the large intestine destroys both transgenes and normal genes. Despite Smith’s claims about the transgene growing in the intestine, the study’s results indicated that while a small level of gene transfer was detected in the ileostomists, the transfer had not occurred during their experiment, and did not increase during the experiment. Furthermore the concentration of the transgene was extremely low and only contained a fragment of the EPSPS gene – the full gene was never detected. In the humans with intact digestive systems, the researchers were unable to detect any of the transgene – preexisting or not – and this did not change during the experiment. The authors additionally stated that “Our results from coculture experiments with transformed bacteria and Caco-2 cells suggest that gene transfer from GM plants to the intestinal epithelium is unlikely to occur.”

The authors concluded that:

* A small portion of the transgenes AND native genes survive the small intestine.
* Both the transgenes and native genes are fully degraded in the large intestine.
* There was some evidence of preexisting gene transfer in the ileostomists, but it represented a very small portion of the microbial population, and the complete transgene had not been transferred.
* It was highly unlikely for gene transfer to alter gastrointestinal function or pose a risk to human health.

So in summary, there is no evidence that humans with normal digestive systems are vulnerable to gene transfer, and some evidence that suggests very low rates of partial gene transfer may occur, but only in ileostomists. As such, unless you’re an ileostomist, Smith’s claims do not apply to you, and even if you are an ileostomist, there is no real reason to be worried.

The next claim was that Bt (an insecticide that, contrary to Smith’s claims, is barely classifiable as toxic) was detected in the blood of pregnant women and their unborn fetuses. This claim is based on the study “Maternal and fetal exposure to pesticides associated to genetically modified foods in Eastern Townships of Quebec, Canada.” (PubMed link), but that study turned out to be completely useless, as demonstrated by refutations from the Food Standards agency for Australia and New Zealand and from Biofortified.

The next claim is a great example of confusing correlation with causation, which appears to be a disease that tends to infect science denialists. While Smith at least does admit that they lack “sufficient research to confirm that GMOs are a contributing factor”, he neglects to mention that this means there is zero supporting research and quite a bit of contradictory research. Whoops.

And, as I already mentioned, the AAEM is not a group that should be trusted, especially when it comes to health claims. Why children are at the most risk is not explained, probably due to the complete lack of evidence.

The IGF-1 cancer link relies on a lack of public knowledge of IGF-1 – a protein present in all milk at low levels, and in the human body at levels ranging from 14 to 102 times the levels present in milk. Smith never explicitly named the amount of IGF-1 that he believes rBST-treated milk contains, but there is no clear proof that an increase (if it exists) even has the potential to affect cancer rates. This is a moot point, as a study demonstrated that rBST-treated and non-rBST milk contain similar levels of IGF-1. Interestingly, the study also demonstrated that organic milk (but not rBST-free conventional milk) contained a slight amount less IGF-1, but there is no evidence that the decrease is anywhere near large enough to influence cancer chances (especially so when you consider how small it is relative to the amount present in the human body).

2. GMOs contaminate―forever.

Smith fails to recognize that gene flow is a natural part of agriculture. No crop is ever 100% pure, which is why USDA Organic guidelines allow for a certain amount of inadvertent contamination. Likewise in the EU, contamination of up to 1% is considered acceptable. This gene flow works both ways – the conventional farmers are also having their crops contaminated with inferior organic plants, and organic farmers are also getting contaminated with the conventional farmer’s plants, as well as other organic farms’ plants. It’s also not difficult to reduce contamination levels in the unlikely event that they are an actual problem for the farmer. Soybeans are one of the more popular transgenic crops, but their method of reproduction means that contamination is extremely low with only minor precautions. While the same is not true for all transgenic crops, proper isolation techniques can still easily result in contamination levels of under 0.5% for corn. Contamination isn’t a new issue either – it’s been a problem for farmers for a very long time. The only difference is that organic farmers may have to give up their premiums if they don’t take extremely basic precautions against contamination that are already recommended by USDA guidelines.

Smith (of course) assumes that the reader is gullible enough to play his “what if” game and too stupid to realize that “what if” is nowhere near reality. What if crops grown with organic production methods turned out to cause cancer? The potential impact is just as huge, and the lack of supporting evidence is no smaller than the lack of supporting evidence for GM crops causing cancer.

Andrew Kniss, Assistant Professor, Weed Biology & Ecology at the University of Wyoming, ruthlessly tore apart Benbrook’s work over at his blog. I’ll summarize his findings here.

Basically, Benbrook did not have NASS data for cotton in the years 2002, 2004, 2006, 2009, and 2011; for soybeans he had nothing past 2006; and for corn he had nothing for the years 2004, 2006, 2007, 2008, 2009, or 2011. Instead of contacting private companies that track this sort of data and purchasing their data, he decided to “forecast” the data for these years.

To his credit, his data for cotton appears to be fairly accurate, as you can see below.

For corn, Benbrook estimates that herbicide use is increasing, despite the data showing a decline.

Last but definitely not least is the soybean data, where Benbrook forecasted five years of data based on only 11 years of observed data. I’ll let the graph speak for itself.

Benbrook failed to distinguish between herbicide tolerant and insect resistant plants, lumping them together under the generalized and highly misleading label of “GE Crops”. Benbrook also used the term GE crops multiple times when he should have referred to herbicide resistant crops.

Benbrook also completely ignored the relative environmental toxicity of glyphosate, which is far lower than many alternatives.

Benbrook also ignored the non-biotech herbicide resistant crops, despite how they’re just as relevant to herbicide use with resistant crops.

PG Economics also released a report on the study, where the study was criticized for a variety of reasons, including for overstating herbicide use by 63.4 million pounds (not exactly a small error!). Further criticisms included the failure to acknowledge environmental benefits from the herbicide resistant crops, a weak approach, and the already mentioned misleading use of NASS usage data.

Last but definitely not least, claiming an increase of pounds without reporting the changing market share of herbicide resistant crops is extremely misleading.

4. Genetic engineering creates dangerous side effects.

There is no proof that this has ever or will ever occur unintentionally.

A study in the Journal of Experimental Botany investigated genetically modified soybeans and food allergies. It found that “Current GM crops, including soybean, have not been shown to add any additional allergenic risk beyond the intrinsic risks already present”, and additionally recognized that “Biotechnology can be used to characterize and eliminate allergens naturally present in crops”.

A 2005 study on the allergenicity of transgenic maize and soya found that “None of the individuals undergoing tests reacted differentially to the transgenic and nontransgenic samples under study. None of the volunteers tested presented detectable IgE antibodies against pure transgenic proteins”.

Another 2007 study on the allergenicity of transgenic soybeans compared to non-transgenic soybeans found that “Soybean endogenous allergen expression does not seem to be altered after genetic modification”.

This evidence suggests that current transgenic food does NOT increase levels of allergens.

But what about the toxins?

A 2012 review of 12 long-term studies (up to 2 years in duration) and 12 multigenerational studies (from 2 to 5 generations) found that “Results from all the 24 studies do not suggest any health hazards and, in general, there were no statistically significant differences within parameters observed”.

There are a huge amount of studies on these foods. Let’s take a look at a few more of them to evaluate the claims of toxin danger.

This 2005 study on MON863 Bt corn found that “Overall, performance was not negatively affected in the corn residue grazing or feedlot experiments, suggesting the corn rootworm-protected hybrid (event MON 863) is similar to conventional, nontransgenic corn grain and residues when utilized by beef cattle”.

This 2003 study on MON863 (Bt) and MON810 (Bt) + MON863 (Bt) in broilers. They concluded that “Broilers overall performed consistently and had similar carcass yields and meat compositions when fed diets containing MON863 corn or MON810 x MON863 corn as compared with their respective nontransgenic control and commercial diets, supporting a conclusion of similar feeding values among diets”.

This 2005 study on Bt176 (Bt) corn and quails over ten generations found that “Feeding of diets containing genetically-modified corn did not significantly influence health and performance of quails nor did it affect DNA-transfer and quality of meat and eggs of quails compared with the isogenic counterpart”.

This 2003 study on Bt11 (Bt) corn in broilers concluded that “It was clear that the transgenic corn had no deleterious or unintended effects on production traits of broiler chickens in this study”.

Ironically, Bt actually reduces the amount of toxins present by reducing insect damage, which in turn reduces the amount of mycotoxins in said Bt corn. This paper estimates that Bt corn’s reduction of the mycotoxins fumonisin and aflatoxin in the US provides a benefit of 23 million dollars annually.

If anything, the anti-GMO activists are acting like the tobacco industry acted. When overwhelming scientific evidence showed that tobacco use was harmful and addictive, the tobacco industry used every trick in the book to suppress this data and to confuse people. Likewise, both the tobacco industry and the anti-GMO activists have cherry picked data, ignored vast quantities of peer-reviewed research, published an endless stream of propaganda, lied constantly about the data, and did their best to suppress any research that contradicted or refuted their narrative.

In the end, biotechnology has science on its side, and the tobacco industry doesn’t. Opposition to biotechnology is thus inherently anti-scientific.

The independent scientist rhetoric is a favorite of the anti-GMO crowd. Too bad that many of the scientists aren’t actually independent (like Seralini), and that the independent scientists who don’t produce junk science are never cited by Smith and his fans.

7. Independent research and reporting is attacked and suppressed.

Biotechnology opponents are among the first to cry “oppression” when their lies are exposed by critics. This is merely a tactic used in an attempt to discredit criticism of flawed studies. Andrew Wakefield used the same tactic when his paper was ripped apart by the medical community.

8. GMOs harm the environment.

Once again, Smith relies on public ignorance to make a point. The herbicide glyphosate, considered by most people to be “the” GMO herbicide (probably due to widespread adoption of glyphosate resistant crops), has a LD50 similar to salt. It does a great job of killing weeds, but has great difficulty killing other things.

GM crops actually tend to increase overall regional biodiversity. Even with this in mind, biodiversity isn’t what feeds people, high yielding crops are. You can plant 500 different species of corn in one field if you’re extremely concerned about specific crop biodiversity, but if overall regional biodiversity is poor and your yields even poorer, what’s the advantage?

As for eliminating Monarch habitat, GM crops are not at fault, agriculture is. Milkweed is a weed, and herbicide resistant crops just happen to be designed so that weeds are easier to eliminate. They are by no means the only way to eliminate milkweed, as many other crops are sprayed with herbicides that also kill milkweed. Additionally, the science is a bit flimsy.

Roundup has quite a bit of junk research on it, but the research being (indirectly) cited here by Seralini appears to be research done with extremely high doses of Roundup (or glyphosate), not realistic doses. A very comprehensive risk assessment on Roundup specifically concluded that it does not pose a realistic health risk to humans.

To put dosage in perspective, the average human in the US probably consumes less than 0.1mg of glyphosate in their food every day. That is a ridiculously tiny amount of glyphosate!

The canola example isn’t useful either. Canola as a vector for herbicide resistant genes is overthinking the issue – it’s easier for weeds to just evolve resistance to the herbicide (although that will change when multiple herbicide resistant crops are commercialized). Sure, canola itself can be a weed, but is that really proof that GMOs “harm the environment”? Herbicide resistance is a problem that by no means is unique to genetically modified crops.

9. GMOs do not increase yields, and work against feeding a hungry world.

The IAASTD report is ridiculously flawed piece of unscientific propaganda that downplayed biotechnology, despite how the evidence contradicted virtually every claim made in the report. Several authors dropped out before the report was completed, leaving a small group of writers with little experience of biotech, and at least one of the writers has a history of producing anti-biotech propaganda. The report contained very little scientific information, and had basically become a soapbox for the organic industry’s supporters. It was a complete failure, and has been criticized by numerous credible sources, including a Nature article.

When you take a look at the scientific literature, the depth of the IAASTD report’s lies becomes very obvious. Organic yields are up to 34% lower, but the average yield gap is around 20% – and increasing!

10. By avoiding GMOs, you contribute to the coming tipping point of consumer rejection, forcing them out of our food supply.

Perhaps if there wasn’t such fierce opposition to the technology the biotech companies would be interested in investing in improvements that improve the food directly. The strict regulatory process and limited consumer acceptance isn’t helping either, no thanks to scare media like Smith’s website. There are some crops in the approval pipeline that fit this criteria – Simplot’s Innate potato (nonbrowning, reduced asparagine content) and the Arctic apples (nonbrowning). Golden Rice also deserves a mention, as it will directly benefit people in impoverished nations.

4 thoughts on “A refutation of the IFRT’s “10 Reasons to Avoid GMOs””

I am nothing more than a bored student, a skeptic, and a rationalist. My credentials are not relevant, what is relevant is the quality of the sources I cite. The only other things I’ve written that are worth reading are on rationalwiki, you can see my contrib list here: http://rationalwiki.org/wiki/Special:Contributions/Firemylasers

Thanks! Sorry about the delay in approving this comment, I don’t use this blog frequently and the notification email WordPress was supposed to send never arrived due to some mildly screwed up email notification settings on my servers.